# Directional Drilling Calc. vs Quail Tools

The clearest difference is review sentiment: Quail Tools at 100% against Directional Drilling Calc.'s 0%. Quail Tools also leads on price (Free vs $0.99) and rating (5.0 vs 1.0). On ads, in-app purchases, device support and iOS requirement there is nothing between them.

Quail Tools is free to download; Directional Drilling Calc. costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Quail Tools holds the better App Store score, 5.0 against 1.0. That said, the two scores are not equally well evidenced: Quail Tools has 22 ratings behind it against 4, so its average is the more settled of the two. Written reviews point the same way: 0% of Directional Drilling Calc.'s written reviews are positive against 100% of Quail Tools's.

Directional Drilling Calc. ships an update every 82 months, Quail Tools every 5 weeks. The most recent releases landed on September 4, 2026 and June 1, 2026 respectively.

## The numbers

| Metric | Directional Drilling Calc. | Quail Tools |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| Rating | [1.0 (4 ratings)](https://appshunter.io/ios/app/directional-drilling-calc/id885580803/reviews) | **[5.0 (22 ratings)](https://appshunter.io/ios/app/quail-tools/id1279372123/reviews)** |
| Number of ratings | 4 | **22** |
| Positive reviews | 0.0% of reviews | **100.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 82 months | **Every 5 weeks** |
| Monetization | Paid | **Free** |
| Size | 1 MB | 50 MB |
| Requires iOS | 13.0 | **12.0** |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [zhandos uakanov](https://appshunter.io/developer/625286817) | [Austin Angelle](https://appshunter.io/developer/1801766276) |

## What reviewers say

### Directional Drilling Calc.

[App page](https://appshunter.io/ios/app/directional-drilling-calc/id885580803)

This application provides essential calculations for directional drilling in oil and gas exploration. It offers multiple methods for calculating directional drilling data and dogleg severity between survey points. Designed for ease of use, it supports professionals in the field.

**Highlights:** Angle Averaging Method, Radius of Curvature Method, Balanced Tangential Method, Minimum Curvature Method, Tangential Method, Dogleg severity calculation

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


### Quail Tools

[App page](https://appshunter.io/ios/app/quail-tools/id1279372123)

Access essential specifications for Tubulars, BOPs, and API Casing offline. View detailed data like tool joint OD, make-up torque, and pressure ratings. Share spec sheets when an internet connection is available.

**Highlights:** Offline access to Tubular and BOP specs, API Casing General Information table, Detailed spec sheets for equipment, Shareable spec sheets (online), Save spec sheets to device, Tool joint OD, ID, torque, tensile, BOP pressure rating, bonnet type, operating data

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Directional Drilling Calc. free?

Directional Drilling Calc. costs $0.99, with no in-app purchases.

### Is Quail Tools free?

Quail Tools is free to download, with no in-app purchases.

### Which has better reviews, Directional Drilling Calc. or Quail Tools?

Quail Tools is rated higher. Directional Drilling Calc. averages 1.0 out of 5 from 4 ratings, while Quail Tools averages 5.0 from 22 ratings.

### Do Directional Drilling Calc. or Quail Tools have ads?

Neither Directional Drilling Calc. nor Quail Tools shows ads.

### Which is updated more often, Directional Drilling Calc. or Quail Tools?

Directional Drilling Calc. ships an update every 82 months, and Quail Tools every 5 weeks. Most recently, Directional Drilling Calc. was updated on September 4, 2026 and Quail Tools on June 1, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*